Numerical simulation was carried out to study
the heat transfer, friction factor and thermal performance of
water inside different tubes induced with different twisted
tapes. The purpose is to ascertain which of the tube designs
gives the best performance when compared with the plain tube.
The tubes were under uniform wall heat flux condition and
Reynolds number in the range 5000 ≤ Re ≤ 20000 were
considered. RNG κ − ε equation model was selected for the
numerical simulations and RANS equations were employed to
render the Navier-Stokes equations tractable. The best
performance was obtained when the tube was fitted with
alternate-axis triangular cut twisted tape. Its Nusselt number
and friction factor are respectively 2.07 – 3.33 and 10.65 – 13.1
times better than that of a plain tube and its thermal
performance factor is 1.35 – 1.43 times better than that of the
tube with plain twisted tape
